It's unclear whether the OP is interested in "content mods" (i.e. not just graphical and UI fixes), but if so it might be worth mentioning the ECCP-related projects. I didn't know about them until recently (and consequently haven't had time to look into it much), but the so-called Extended Community Canon Project apparently attempts to flesh out the game world with additional (interconnected and compatible) story/quest content without straying too far from the source material. Examples of major mods include Dark Times, Alley of Murder, Bloodworks, Ser Gilmore Recruitable NPC, Alistair's Royal Wedding (yes, indeed…) and the upcoming Apostate Mage Origin story. Might be work checking out…